Business and Basis of Presentation Supplemental Cash Flow information (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2024	Jun. 30, 2024	Jun. 30, 2023	Dec. 31, 2023	Dec. 31, 2022
Cash and Cash Equivalents, at Carrying Value	$ 24	$ 24	$ 33
Income Taxes Paid		7	6
Restricted Cash	11	11	10	$ 12
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents	97	97	309	274	$ 61
Securities acquired (transferred) in transactions related to Puerto Rico restructurings	0		(1)
Securities acquired (transferred) in connection with financial guarantee commutations		(65)
Long-term Debt [Member]
Interest Paid, Including Capitalized Interest, Operating and Investing Activities		0	50
Variable Interest Entity, Primary Beneficiary [Member]
Restricted Cash	$ 62	$ 62	$ 266	$ 246

Securities acquired (transferred) in connection with financial guarantee commutations

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Securities acquired (transferred) in transactions related to Puerto Rico restructurings

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Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation.

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Amount of cash and cash equivalents, and cash and cash equivalents restricted to withdrawal or usage. Excludes amount for disposal group and discontinued operations. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits. Cash equivalents include, but are not limited to, short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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The amount of cash paid during the current period to foreign, federal, state, and local authorities as taxes on income.

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Amount of cash paid for interest, including, but not limited to, capitalized interest and payment to settle zero-coupon bond attributable to accreted interest of debt discount and debt instrument with insignificant coupon interest rate in relation to effective interest rate of borrowing attributable to accreted interest of debt discount; classified as operating and investing activities.

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Amount of cash restricted as to withdrawal or usage. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits.

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